Operator-assisted telephone service facilities, such as directory assistance, toll service and private branch exchanges, require that the servicing operator handle a large number of similar, (effectively monotonous routine) calls during the operator's work period. In a directory assistance position, where the monotony problem is particularly acute, it has been common practice to provide the operator with a mechanized voice storage and retrieval unit (commonly referred to as an automatic response unit, or ARU) which, when accessed from the operator's terminal position (simultaneously releasing the operator to handle another call), assembles a verbalized response message by stringing together a series of prerecorded or synthesized words, typically comprised of an introductory phrase (such as "The number is") followed by a sequence of numerical digits, and couples this `android-sounding`audio message to an automated call director (switch) for application over the telephone line to the calling party.
Now, although the use of an automatic response unit provides some assistance to the operator, from the customer's standpoint its mechanical sounding voice is not only unattractive (and a confusing change from the voice of the operator), but often, to the customer's ear, is of such inferior quality that the customer stays on the line to hear a repeat of the message or until the operator picks up the call and handles the inquiry directly. In either of these events, there is a delay in providing the intended service, which incurs the penalty of user dissatisfaction and lost revenue. Of course, there are many occasions in which the ARU cannot be used to meet the customer's needs, as in the case of a multiple directory number request and for information other than that which has been previously recorded and stored. Under such circumstances it is necessary for direct operator participation; still, the basic information supply exercise conducted by the operator, e.g. that of retrieving a number or address from a database and delivering (speaking) that information to the customer, is the same as when using the ARU.
Advantageously, a considerable aspect of the problem, particularly the quality of the synthesized message vocalized to the customer, is addressed by the telephone operator voice storage and retrieval system described in U.S. Pat. Nos. 4,623,761, issued Nov. 18, 1986 and 4,697,282, issued Sept. 29, 1987, and assigned to the assignee of the present application. Pursuant to the patented scheme, messages to be played back to the customer are prerecorded (digitized and stored in computer-addressable memory) in the voice of the operator who is on-line during the servicing of the call, so that, when retrieved and synthesized out to the calling party, the played-back messages are effectively indistinguishable from the live voice of the operator, thus presenting a realistic audio message to the subscriber, which not only avoids customer confusion, but reduces revenue-impacting delay time.